JP3273403B2 - Sulfonyl compound and heat-sensitive recording material using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a specific sulfonyl compound and a polyvalent metal salt thereof, and the use of the compound. More specifically, when the compound is used as a developer for a thermosensitive recording material, a high sensitivity is obtained. In addition, the present invention relates to a sulfonyl compound and a polyvalent metal salt thereof which have less background fogging and provide recording characteristics excellent in storage stability of a recorded image, especially excellent in moisture resistance, heat resistance and plasticizer resistance.

[0002]

2. Description of the Related Art Thermosensitive recording materials utilizing a thermal coloring reaction between a basic dye precursor and an electron-accepting developer have been well known. Among them,
As developers, 2,2-bis (4-hydroxy-phenyl) propane and 4-hydroxy-4'-isopropoxy-diphenyl sulfone are well known (for example,
JP-B-3-54655, etc.).

However, heat-sensitive recording materials using these materials are required to be further improved in storage stability of color images, particularly in moisture resistance, heat resistance and plasticizer resistance. An object of the present invention is to provide a recording medium having high sensitivity and less background fogging when used as a developer of a heat-sensitive recording material, and excellent recording stability, particularly excellent in moisture resistance, heat resistance and plasticizer resistance. It is to provide a color developer which can give the following.

[0004]

The present inventors have repeatedly studied to find a developer capable of obtaining a heat-sensitive recording material having high sensitivity and excellent preservability of a recorded image, and as a result, the general formula (1) was obtained. Have been found, and the present invention has been accomplished.

[0005]

[Outside 4] [In the general formula (1), X represents a hydrogen atom or a lower alkyl group, and R ₁ , R ₂ and R ₃ may be the same or different and each represents a hydrogen atom, a halogen atom, a hydroxyl group, or a lower alkyl group. or represents cycloalkyl hexyl group,
R ₄ , R ₅ and R ₆ may be the same or different and each represents a hydrogen atom, a halogen atom, a lower alkyl group,
Represents a hexyl group, R ₇ is a hydrogen atom or

[0006]

[Outside 5] Wherein R ₄ , R ₅ and R ₆ are as defined above. In the definition of the general formula (1), the lower alkyl group preferably has 1 to 4 carbon atoms. In the present invention, a sulfonyl compound represented by the general formula (1) and a polyvalent metal salt thereof are used as a color developer in a thermosensitive recording material mainly containing a basic dye precursor, a color developer and a sensitizer. The present invention relates to a thermosensitive recording material characterized by the following. Specific examples of the compound represented by the general formula (1) according to the present invention include the following compounds.

(1) 2,4-bis (phenylsulfonyl) phenol, (2) 2,4-bis (2-methylphenylsulfonyl) phenol, (3) 2,4-bis (4
-Methylphenylsulfonyl) phenol, (4) 2,
4-bis (4-bromophenylsulfonyl) phenol, (5) 2,4-bis (4-chlorophenylsulfonyl) phenol, (6) 2,4-bis (2,4-dimethylphenylsulfonyl) phenol, (7) 2,4-bis (3,4-dimethylphenylsulfonyl) phenol, (8) 2,4-bis (2,5-dimethylphenylsulfonyl) phenol, (9) 2,4-bis (2,4,
6-trimethylphenylsulfonyl) phenol, (1
0) 2,4-bis (4-ethylphenylsulfonyl) phenol, (11) 2,4-bis (4-isopropylphenylsulfonyl) phenol, (12) 2,4-bis (4-cyclohexylphenylsulfonyl) phenol, (13) 2,4-bis (phenylsulfonyl) -5
-Methylphenol, (14) 2,4-bis (2-methylphenylsulfonyl) -5-methylphenol, (1
5) 2,4-bis (4-methylphenylsulfonyl)-
5-methylphenol, (16) 2,4-bis (4-isopropylphenylsulfonyl) -5-methylphenol, (17) 2,4-bis (2,4-dimethylphenylsulfonyl) -5-methylphenol, ( 18) 2, 4
-Bis (2,5-dimethylphenylsulfonyl) -5-
Methylphenol, (19) 2,4-bis (phenylsulfonyl) -5-ethylphenol, (20) 2,4-
Bis (4-methylphenylsulfonyl) -5-ethylphenol, (21) 2,4-bis (4-ethylphenylsulfonyl) -5-ethylphenol, (22) 2,4
-Bis (2,4 dimethylphenylsulfonyl) -5-ethylphenol, (23) 2,4-bis (2,5-dimethylphenylsulfonyl) -5-ethylphenol,
(24) 2,4-bis (phenylsulfonyl) -5-isopropylphenol, (25) 2- (4-methylphenylsulfonyl) -4- (phenylsulfonyl) phenol, (26) 2- (4-ethylphenylsulfonyl) )
-4- (phenylsulfonyl) phenol, (27) 2
-(4-isopropylphenylsulfonyl) -4- (phenylsulfonyl) phenol, (28) 2- (2,5
-Dimethylphenylsulfonyl) -4- (phenylsulfonyl) phenol, (29) 2- (2,4-dimethylphenylsulfonyl) -4- (phenylsulfonyl) phenol, (30) 2- (3,4-dimethylphenylsulfonyl) ) -4- (phenylsulfonyl) phenol;
(31) 2- (4-chlorophenylsulfonyl) -4-
(Phenylsulfonyl) phenol, (32) 2- (4
-Bromophenylsulfonyl) -4- (phenylsulfonyl) phenol, (33) 2- (phenylsulfonyl) -4- (4-methylphenylsulfonyl) phenol, (34) 2- (phenylsulfonyl) -4- (4-
Ethylphenylsulfonyl) phenol, (35) 2-
(Phenylsulfonyl) -4- (4-isopropylphenylsulfonyl) phenol, (36) 2- (phenylsulfonyl) -4- (2-methylphenylsulfonyl)
Phenol, (37) 2- (phenylsulfonyl) -4
-(2,5-dimethylphenylsulfonyl) phenol, (38) 2- (phenylsulfonyl) -4- (2,
4-dimethylphenylsulfonyl) phenol, (3
9) 2- (phenylsulfonyl) -4- (3,4-dimethylphenylsulfonyl) phenol, (40) 2-
(Phenylsulfonyl) -4- (4-chlorophenylsulfonyl) phenol, (41) 2- (phenylsulfonyl) -4- (4-bromophenylsulfonyl) phenol, (42) 2- (4-methylphenylsulfonyl)
-4- (phenylsulfonyl) -5-methylphenol, (43) 2- (4-chlorophenylsulfonyl)-
4- (phenylsulfonyl) -5-methylphenol,
(44) 2- (4-bromophenylsulfonyl) -4-
(Phenylsulfonyl) -5-methylphenol, (4
5) 2- (phenylsulfonyl) -4- (4-methylphenylsulfonyl) -5-methylphenol, (46)
2- (phenylsulfonyl) -4- (4-chlorophenylsulfonyl) -5-methylphenol, (47) 2-
(Phenylsulfonyl) -4- (4-bromophenylsulfonyl) -5-methylphenol, (48) 2- (4
-Methylphenylsulfonyl) -4- (phenylsulfonyl) -5-ethylphenol, (49) 2- (4-chlorophenylsulfonyl) -4- (phenylsulfonyl) -5-ethylphenol, (50) 2- (4- Bromophenylsulfonyl) -4- (phenylsulfonyl)
-5-ethylphenol, (51) 2- (phenylsulfonyl) -4- (4-methylphenylsulfonyl) -5
-Ethylphenol, (52) 2- (phenylsulfonyl) -4- (4-chlorophenylsulfonyl) -5-ethylphenol, (53) 2- (phenylsulfonyl)
-4- (4-bromophenylsulfonyl) -5-ethylphenol, (54) 2- (4-methylphenylsulfonyl) -4- (phenylsulfonyl) -5-isopropylphenol, (55) 2- (phenylsulfonyl) −
4- (4-methylphenylsulfonyl) -5-isopropylphenol, (56) 4,4'-dihydroxy-5
-(Phenylsulfonyl) diphenylsulfone, (5
7) 4,4'-dihydroxy-5,5'-bis (phenylsulfonyl) diphenyl sulfone, (58) 4,4 '
-Dihydroxy-5- (4-methylphenylsulfonyl) diphenylsulfone, (59) 4,4'-dihydroxy-5,5 '-(4-methylphenylsulfonyl) diphenylsulfone, (60) 4,4'-dihydroxy-
5,5'-bis (4-chlorophenylsulfonyl) diphenyl sulfone, (61) 4,4'-dihydroxy-
5,5'-bis (4-bromophenylsulfonyl) diphenylsulfone, (62) 2,4bis (2,3-dimethylphenylsulfonyl) -5-methylphenol, (6
3) 2,4bis (2,4-dimethylphenylsulfonyl) -5-methylphenol, (64) 2,4bis (2,5-dimethylphenylsulfonyl) -5-methylphenol, (65) 2,4bis (3,4-dimethylphenylsulfonyl) -5-methylphenol.

Particularly preferred of these compounds are (1), (3), (5) to (8), (10) to (1)
1), (13), (15), (19), (25) to (2)
6), (28) to (31), (33) to (34), (3)
7) to (40) and (56) to (57). In the polyvalent metal salt of the above compound, the metal is preferably zinc, magnesium, strontium, aluminum, iron, cobalt, nickel and titanium, and among them, zinc, magnesium, aluminum, iron, nickel and titanium are particularly preferable.

Next, a method for producing the sulfonyl compound represented by the general formula (1) will be described. That is, the reaction is carried out in the presence of a Friedel-Crafts catalyst, and specifically, there are three methods.

[0010]

[Outside 6] In the general formula (3), Z represents a halogen atom, and X has the same meaning as in the general formula (1). General formula (4)
In the formula, R ₁ , R ₂ and R ₃ have the same meaning as in formula (1). In the general formula (5), Z represents the same meaning as in the general formula (3), and X, R ₁ , R ₂
And R ₃ have the same meaning as in formula (1).

[0011]

[Outside 7] However, in the case of this method, in the general formula (1),

[0012]

[Outside 8] And R ₇ is a hydrogen atom.

[0013]

[Outside 9] In the general formula (6), X has the same meaning as in the general formula (1). In the general formula (7), R ₁ , R ₂ and R ₃ represent the same meaning as in the general formula (1). However, in the case of this method, the general formula (1) can be obtained by the method (I)
Represents the same meaning as in

[0014]

[Outside 10] In the general formula (8), X, R ₁ , R ₂ and R ₃ have the same meaning as in the general formula (1). In the general formula (9), m represents 1 or 2, and R ₄ , R ₅ and R ₆ have the same meaning as in the general formula (1).

The catalyst in the present reaction is a Friedel-Crafts catalyst, preferably iron chloride, aluminum chloride, zinc chloride, magnesium chloride or the like.

Next, the heat-sensitive recording material according to the present invention will be described. As described above, the heat-sensitive recording material of the present invention is a heat-sensitive recording material in which a heat-sensitive recording layer containing a basic dye precursor, a color developer and a sensitizer is provided on a support. Wherein a compound represented by the general formula (1) or a polyvalent metal salt thereof is used. The developer is a compound represented by the general formula (1) or a polyvalent metal salt thereof alone or in combination of one or more, and at least one of the above-described developers and the general formula (2)

[0017]

[Outside 11] [In the general formula (2), R ₈ and R ₉ may be the same or different and each represents a hydrogen atom, a lower alkyl group or a lower alkylene group, and R ₁₀ represents a hydrogen atom or a linear or branched lower alkyl group. Y represents a sulfonyl group, a lower alkylene group or a lower alkylidene group, and n represents 0 or 1. The object can be achieved by combining with at least one diphenyl derivative represented by the following formula: In the definition of the general formula (2), the lower alkyl group preferably has 1 to 4 carbon atoms, and the lower alkylene group preferably has 1 to 4 carbon atoms.

The diphenyl derivatives represented by the general formula (2) include 2,2-bis (4-hydroxy-phenyl) propane, 4-hydroxy-4'-isopropoxy-diphenyl sulfone, and 4,4'- Dihydroxy-diphenylsulfone, bis (3-allyl-4-hydroxy-
Phenyl) sulfone, 4-hydroxy-2 ', 5'-dimethyl-diphenylsulfone, 2-methyl-4-hydroxy-diphenylsulfone and the like are listed.

Next, the method of using the present compound in combination as a color developer will be described in detail.

(1) The number of compounds to be combined is two or more. However, if the number is too large, it becomes complicated, and two or three are most preferable.

(2) It is necessary for the combination to always contain the sulfonyl compound represented by the general formula (1) in order to achieve the object.

(3) The combination ratio of at least one compound is at least 1 part by weight, preferably at least 5 parts by weight, based on 100 parts by weight of the total color developer.

(4) The compounding and preparing method is as follows: (a) a method of mixing and preparing a compound obtained by pulverizing each compound at a desired ratio; (b) a method of mixing and pulverizing at a desired ratio during pulverization; c) Any method of pulverizing a material which has been previously adjusted to a desired ratio by a recrystallization method may be used.

The polyvalent metal used as a developer is a compound represented by the general formula (1), zinc, magnesium,
It can be prepared separately from a water-soluble salt of a polyvalent metal such as strontium, aluminum, iron, cobalt, nickel and titanium, and used separately from the compound represented by the general formula (1) in the thermosensitive coloring layer. The purpose can be achieved by coexisting oxides, hydroxides, carbonates, sulfates and the like of the valent metal. The total amount of the compound used as a developer is 50 to 6 parts by weight per 100 parts by weight of the basic dye.
00 parts by weight, preferably 100 to 400 parts by weight.

Next, basic dyes and sensitizers used in the recording material according to the present invention will be described.

The basic dyes include triarylmethane compounds, diarylmethane compounds, pyridine compounds, spiro compounds, rhodamine-lactam compounds,
Examples thereof include a fluoran compound, an indolylphthalide compound, and a fluorene compound. Among them, 3-N,
N-dibutylamino-6-methyl-7-anilinofluoran, 3-N, N-diethylamino-6-methyl-7-
Anilinofluorane, 3- (N-isopentyl-N-ethyl) -6-methyl-7-anilinofluoran, 3-
(N-cyclohexyl-N-methyl) -6-methyl-7
-Anilinofluoran, 3-N, N-diethyl-6-chloro-7-anilinofluoran and the like are exemplified as typical examples. These basic dyes may be used alone or as a mixture of two or more kinds for the purpose of adjusting the color tone of a color-developed image or obtaining a multicolor heat-sensitive recording material.

Next, examples of the sensitizer include nitrogen-containing compounds, ester compounds, hydrocarbon compounds, ether compounds, and sulfone compounds. Among them, β-naphthylbenzyl ether, stearic acid amide, 4-benzyloxybenzoic acid benzyl ester, dibenzyl oxalate, di-P-methylbenzyl oxalate, bis (4-methylphenyl) carbonate, 4-benzylbiphenyl, n −
Terphenyl, 1,2-bis (3-methylphenoxy)
Ethane, 1,2-bis (phenoxy) ethane, diphenylsulfone, 3,3 ', 4,4'-tetramethyl-diphenylethane and the like are exemplified as typical examples. These sensitizers may be used alone or in combination of two or more. The sensitizer is used in an amount of 50 to 800 parts by weight, preferably 100 to 400 parts by weight, based on 100 parts by weight of the basic dye.

The heat-sensitive recording paper according to the present invention can be manufactured by a known method, and it is not necessary to adopt any special method. In general, for example, a basic dye, a developer,
Sensitizer, pigment, metal soap, wax, surfactant,
A coating liquid can be prepared by pulverizing and dispersing an antifoaming agent or the like in an aqueous medium containing a water-soluble binder to a particle size of usually 3 μm or less, preferably 1.5 μm or less by means of a ball mill, sand mill or the like. .

Examples of the above pigments include calcium carbonate, magnesium carbonate, titanium oxide, kaolin, silica, amorphous silica, zinc oxide and the like.

Examples of the metal soap include zinc stearate and calcium stearate.

As the wax, paraffin wax,
Examples include microcrystalline wax and polyethylene wax.

Examples of the surfactant include an alkali metal salt of sulfosuccinic acid, an alkali metal salt of alkylbenzenesulfonic acid, and a sodium salt of lauryl alcohol sulfate.

In the heat-sensitive recording material of the present invention, the heat-sensitive recording layer can be formed by a conventionally known technique, and the forming method is not particularly limited. For example,
The coating solution for the heat-sensitive recording layer can be coated on a support with a suitable coating device such as an air knife coater, a blade coater, a bar coater, a gravure coater, a curtain coater, a wire bar and the like, and dried to form a recording layer. .
There is no particular limitation on the application amount of the coating liquid,
Generally 0.5 to 12 gr / m2 in dry weight with respect to the support surface
² , preferably in the range of 1.0 to 8.0 gr / m ² . As the support, paper, plastic sheet, synthetic paper and the like are used.

[0034]

The present invention will be described below with reference to examples. (Example 1) 1-chloro-2,
309 gr of 4-sulfonylbenzene dichloride, benzene 2
0 gr and 2 gr of anhydrous ferric chloride, and heated to 150 ° C. while stirring under a nitrogen gas atmosphere.
Over a period of 0 hours, 150 gr of benzene was added dropwise. On the way, crystals were formed. After aging at the same temperature for 2 hours after dropping,
500 gr of benzene was slowly charged. Crystals precipitated at room temperature were separated by filtration, and the crystals were further washed with 1 liter of methanol to obtain 280 gr of white crystal powder. Melting point 19
6 ° C.

Next, 196 gr of this product and 600 g of a 10% aqueous sodium hydroxide solution were placed in an autoclave reactor.
and the hydrolysis reaction was continued at 200 ° C. and 15 kg / cm ² for 5 hours. After cooling, 10% diluted sulfuric acid was slowly added dropwise with stirring to adjust the pH to 6. The precipitated crystal was separated by filtration, and the crystal was further purified by recrystallization with n-butanol.
160 gr of white crystalline powder was obtained. 157 ° C. IR analysis, H-NMR analysis and elemental analysis of this product (Table 1)
From the results, it was confirmed that the product was 2,4-bis (phenylsulfonyl) phenol.

[0036] (The potassium bromide tablet method, the same applies hereinafter) The infrared absorption spectrogram of this product is shown in FIG.
1 to 16, the vertical axis indicates transmittance (%),
The horizontal axis indicates the wave number (cm ^-1 ).

Example 2 Into a 1-liter reactor, 94 gr of phenol and 1 gr of anhydrous ferric chloride were charged and heated to 80 ° C. with stirring under a nitrogen gas atmosphere, and 370 gr of benzenesulfonyl chloride was added at the same temperature. It was added dropwise over 2 hours. After completion of the dropwise addition, the mixture was maintained at the same temperature for 5 hours, then slowly heated to 150 ° C., and maintained at the same temperature for 24 hours to complete the reaction.

Next, the reaction solution obtained by the above method was poured into 1000 gr of a 5% aqueous sodium hydroxide solution,
, And filtered. The filtrate is then added to 9
Crystals were precipitated by slowly adding dropwise to 1000 g of 6% diluted sulfuric acid adjusted to 0 ° C while stirring. The crystal was separated by filtration, washed with 1 liter of water, and then dissolved by heating in 1 liter of methyl isobutyl ketone.
00 ml was added and the oil was washed with water. The oil was separated, and the oil was washed twice with 100 ml of water. Next, water in the oil was removed by azeotropic dehydration, and then decolorized using 3 gr of activated carbon and 1 gr of activated clay. The solution thus obtained was cooled to room temperature to obtain 310 gr of white crystalline powder. 157 ° C. IR of this thing
From the results of analysis, H-NMR analysis and elemental analysis (Table 2), it was confirmed that the product was 2,4-bis (phenylsulfonyl) phenol.

[0039] FIG. 2 shows the infrared absorption spectrogram of this product.

Examples 3 to 10 The same operation as in Example 2 was carried out except that the phenol, benzenesulfonyl chloride and methyl isobutyl ketone used in Example 2 were changed to the compounds and amounts shown in Table 3, respectively. Table 4 shows the results.

[0041]

[Outside 12]

[0042]

(Example 11) In a 2-liter reactor, 4
-234 gr of (phenylsulfonyl) phenol, 60 gr of tosyl chloride and 1 gr of anhydrous ferric chloride were charged, and the temperature was slowly raised to 100 ° C while stirring under a nitrogen gas atmosphere. After reacting at the same temperature for 5 hours, the generation of hydrochloric acid gas became weaker. To this, 150 g of tosyl chloride was further added dropwise at the same temperature over 5 hours, and after completion of the addition, the temperature was gradually raised to 150 ° C., and the temperature was increased to 24 hours. The reaction continued. Next, the reaction solution obtained by the above method was
Into a 1000% aqueous sodium hydroxide solution,
After stirring at 95 ° C. for 2 hours, the mixture was filtered. The filtrate was then slowly dropped into 1000 gr of 6% diluted sulfuric acid adjusted to 90 ° C. while stirring to precipitate crystals. The crystals were separated by filtration, washed with 1 liter of water, and dissolved by heating in 1 liter of toluene. 100 ml of water was added to wash the toluene oil. The oil was separated, and the oil was washed twice with 100 ml of water.
Next, after removing water in the oil by azeotropic dehydration, activated carbon 3 gr
And decolorized using 1 gr of activated clay. The solution thus obtained was cooled to obtain 300 gr of white crystalline powder. 158 ° C. IR analysis, H-NMR
From the results of analysis and elemental analysis (Table 5), this product was found to be 2- (4
-Methylphenylsulfonyl) -4- (phenylsulfonyl) phenol was confirmed.

[0044] FIG. 11 shows an infrared absorption spectrogram of this product.

Example 12 In a 1-liter reactor,
25 gr of 4,4'-dihydroxydiphenyl sulfone,
180 g of benzenesulfonyl chloride and 0.1 g of anhydrous ferric chloride were charged, and the temperature was slowly raised to 120 ° C. while stirring under a nitrogen gas atmosphere. 2 at the same temperature
After reacting for 4 hours, the generation of hydrochloric acid gas weakened and a crystal precipitated. The crystal was separated by filtration, and the crystal was slurry-washed with 500 ml of 5% hydrochloric acid and further washed with 1 liter of water. And the crystallized product was converted to methanol: water = 98: 2.
(Volume ratio) Recrystallization was performed with 500 ml of the mixed solution to obtain 30 gr of white crystalline powder. Melting point 247 [deg.] C. From the results of IR analysis, H-NMR analysis and elemental analysis (Table 6), it was confirmed that the product was 4,4'-dihydroxy-5,5'-bis (phenylsulfonyl) diphenylsulfone.

[0046] FIG. 12 shows the infrared absorption spectrogram of this product.

(Embodiment 13)
4- (4-methylphenylsulfonyl) phenol 24 instead of 234 gr of (phenylsulfonyl) phenol
Example 11 was repeated except that 8 gr was used, 60 g of benzenesulfonyl chloride was used instead of 60 gr of tosyl chloride, and 134 gr of benzenesulfonyl chloride was used instead of 150 gr of tosyl chloride. Final product yield 310 gr, melting point 155.
C and infrared absorption spectrograms are as shown in FIG. 13. From the analysis results, it was confirmed that the product was 2- (phenylsulfonyl) -4- (4-methylphenylsulfonyl) phenol.

Example 14 Example 11 was repeated except that 60 gr of tosyl chloride was replaced with 60 gr of 4-chlorobenzenesulfonyl chloride and 172 gr of 4-chlorobenzenesulfonyl chloride was used instead of 150 gr of tosyl chloride. The same operation and analysis were performed. The yield of the final product was 330 gr, the melting point was 135 ° C., and the infrared absorption spectrogram was as shown in FIG. 14. From the analysis results, the product was 2- (4-chlorophenylsulfonyl) -4- (phenylsulfonyl) phenol. It was confirmed that.

Example 15 In a 1-liter reactor,
2,4-bis (phenylsulfonyl) phenol 50g
r, water 500 gr, 5% sodium hydroxide aqueous solution 107
After gr was charged and stirred at 60 ° C. for 5 hours, 250 gr of a 10% aqueous solution of zinc sulfate (heptahydrate) was added dropwise at the same temperature over 2 hours. After dropping, the mixture was aged for 2 hours at the same temperature, and the precipitated crystal was separated by filtration. The crystal was washed with 1 liter of water and dried to obtain 52.5 gr of white crystalline powder.
The product did not melt up to 250 ° C. IR of this thing
From the results of analysis and atomic absorption spectrum analysis, this product
It was confirmed to be a zinc salt of 2,4-bis (phenylsulfonyl) phenol.

FIG. 15 shows an infrared absorption spectrogram of this product.

(Example 16) In a 1-liter reactor,
50 g of 2,4-bis (phenylsulfonyl) -5-ethylphenol, 500 g of water and 99 g of a 5% aqueous sodium hydroxide solution were charged and dissolved by stirring at 60 ° C. for 5 hours.
r was added dropwise over 2 hours. After dropping, the resulting crystals were aged for 2 hours at the same temperature, and the precipitated crystals were separated by filtration. The crystals were washed with 1 liter of water and dried to obtain 50 gr of white crystalline powder. Melting point 220 [deg.] C.

From the results of IR analysis and atomic absorption spectrum analysis of this product, it was confirmed that the product was a magnesium salt of 2,4-bis (phenylsulfonyl) -5-ethylphenol. FIG. 16 shows the infrared absorption spectrogram of this product.

Example 17 Preparation of Basic Dye Dispersion A solution of 20 g of 3-N, N-dibutylamino-6-methyl-7-anilinofluoran in 5% polyvinyl alcohol (manufactured by Kuraray; trade name PVA) -117) 80 g of aqueous solution
The mixture was pulverized for 20 hours using a ball mill in the same manner as above to prepare a basic dye dispersion having an average particle size of 0.6 μm.

Preparation of Developer and Sensitizer Dispersion 20 gr of 2,4-bis (4-methylphenylsulfonyl) phenol and 20 gr of 1,2-bis (3-methylphenoxy) ethane were added to polyvinyl alcohol at a concentration of 5%. (PVA-117) An aqueous developer / sensitizer dispersion having an average particle diameter of 0.6 μm was prepared by pulverizing in a 60 g aqueous solution using a ball mill for 20 hours.

Preparation of Pigment Dispersion Calcium Carbonate (manufactured by Shiraishi Kogyo; trade name Univer 70) 3
0 gr, 70 gr of water and 1 gr of a 40% strength aqueous sodium hexametaphosphate solution were stirred for 15 minutes with a homogenizer having a rotation speed of 15,000 rpm to prepare a pigment dispersion.

Preparation of Coating Solution for Heat-Sensitive Layer 3 gr of the above basic dye dispersion, 6 gr of the developer / sensitizer dispersion, and 7 gr of the pigment dispersion, and 31% hydrin Z-7 (manufactured by Chukyo Yushi Co., Ltd.) (Commercial name) 1.0 gr and 15 gr of water were mixed to obtain a thermosensitive layer coating solution.

Preparation of heat-sensitive recording paper A heat-sensitive layer coating solution was applied on a paper support using a wire bar so that the weight of the heat-sensitive layer after drying was 5 gr / m ^2, and dried in an oven at 60 ° C. Thereafter, a calendering process was performed so that the smoothness became 200 seconds (Beck method).

Examples 18 to 35 Developer 2,4-bis (4-methylphenylsulfonyl) used in Example 17
The same operation as in Example 17 was carried out except that the following developer was used instead of phenol 20 gr. Table 7 shows the developers used and their weights.

[0059]

[Outside 13]

Example 36 A developer / sensitizer dispersion was obtained by mixing equal amounts of the developer / sensitizer dispersions obtained in Examples 17 and 20, respectively, to obtain a developer / sensitizer dispersion. The same operation as in 17 was performed.

(Example 37) 2,4-bis (4-methylphenylsulfonyl) phenol: 2,4-bis (phenylsulfonyl)
Mixture 20 wherein -5-methylphenol = 50: 50
The same operation as in Example 17 was performed, except that gr was used as a developer.

(Comparative Examples 1-2) Example 17 was repeated except that the following developer was used in place of 20 gr of the developer 2,4-bis (4-methylphenylsulfonyl) phenol used in Example 17. The same operation was performed.

Comparative Example 1 2,2-bis (4-hydroxy-phenyl) propane 20 gr Comparative Example 2 2,2-bis (4-hydroxy-phenyl) propane 10 gr 4-hydroxy-4'-isopropoxy-diphenylsulfone 10 gr The thermal recording papers obtained in Examples 17 to 37 and Comparative Examples 1 and 2 were subjected to a printing test under the copy mode conditions of a FUJTSU FAX FF1700RX machine, and the following performance comparison tests were performed. Table 8 shows the results.

Performance comparison test Print density The print density was measured using a Macbeth densitometer.

Heat Resistance Test Skin: Stain on the skin after standing at 60 ° C. for 24 hours was visually observed according to the following criteria.

：: no change Δ: slightly colored
×: markedly colored printing; After the printing paper was left at 60 ° C. for 24 hours, the remaining percentage of printing density (%) indicated by the following criteria was measured.

Residual printing density (%) = (printing density after storage / printing density before storage) × 100 Moisture resistance test Background: Dirt on the background after standing at 40 ° C. and 90% humidity for 24 hours is heat resistant. The results are shown in accordance with the standard of the soil stain test.

Printing: printing paper was heated to 40 ° C. and 90% humidity for 24 hours.
After standing for a period of time, it was expressed according to the heat resistant print remaining rate (%).

Plasticizer test A printing paper was wrapped around the outer periphery of a glass bottle, and a high wrap V-450 (trade name, manufactured by Mitsui Toatsu Chemicals Co., Ltd.) was wrapped three times thereon and left at 40 ° C. for 2 hours. And the heat-resistant residual print ratio (%).

[0070]

[Outside 14]

As is evident from the data in Table 8, the heat-sensitive recording material according to the present invention has excellent coloring properties, has little background fogging over time, and has a storage stability of recorded images, especially heat resistance, moisture resistance and plastic resistance. It turns out that it is excellent in agent property.

[0072]

According to the present invention, there is provided a heat-sensitive recording material having high sensitivity, little background fogging over time, and excellent storage stability of recorded images, especially heat resistance, moisture resistance and plasticizer.

[Brief description of the drawings]

FIG. 1 is an infrared absorption spectrogram of the compound obtained in Example 1.

FIG. 2 is an infrared absorption spectrogram of the compound obtained in Example 2.

FIG. 3 is an infrared absorption spectrogram of the compound obtained in Example 3.

FIG. 4 is an infrared absorption spectrogram of the compound obtained in Example 4.

FIG. 5 is an infrared absorption spectrogram of the compound obtained in Example 5.

FIG. 6 is an infrared absorption spectrogram of the compound obtained in Example 6.

FIG. 7 is an infrared absorption spectrogram of the compound obtained in Example 7.

FIG. 8 is an infrared absorption spectrogram of the compound obtained in Example 8.

FIG. 9 is an infrared absorption spectrogram of the compound obtained in Example 9.

FIG. 10 is an infrared absorption spectrogram of the compound obtained in Example 10.

FIG. 11 is an infrared absorption spectrogram of the compound obtained in Example 11.

FIG. 12 is an infrared absorption spectrogram of the compound obtained in Example 12.

FIG. 13 is an infrared absorption spectrogram of the compound obtained in Example 13.

FIG. 14 is an infrared absorption spectrogram of the compound obtained in Example 14.

FIG. 15 is an infrared absorption spectrogram of the compound obtained in Example 15.

FIG. 16 is an infrared absorption spectrogram of the compound obtained in Example 16.

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁷ Identification symbol FI C07C 315/00 C07B 61/00 300 // C07B 61/00 300 B41M 5/18 108 (56) References JP-A-58-150561 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C07C 317/00 B41M 5/00 C07C 315/00 CA (STN) REGISTRY (STN)

Claims (6)

(57) [Claims] 1. General formula (1) [In the general formula (1), X represents a hydrogen atom or a lower alkyl group, and R ₁ , R ₂ and R ₃ may be the same or different and each represents a hydrogen atom, a halogen atom, a hydroxyl group, or a lower alkyl group. or represents cycloalkyl hexyl group,
R ₄ , R ₅ and R ₆ may be the same or different and each represents a hydrogen atom, a halogen atom, a lower alkyl group,
Represents a hexyl group, and R ₇ is a hydrogen atom or Wherein R ₄ , R ₅ and R ₆ are as defined above. A sulfonyl compound and a polyvalent metal salt thereof. 2. The sulfonyl compound represented by the general formula (1) is 2,4-bis (phenylsulfonyl) phenol, 2,4-bis (4-methylphenylsulfonyl) phenol, 2,4-bis (4- Ethylphenylsulfonyl) phenol, 2,4-bis (4-isopropylphenylsulfonyl) phenol, 2,4-bis (2,5-
Dimethylphenylsulfonyl) phenol, 2,4-bis (2,4-dimethylphenylsulfonyl) phenol, 2,4-bis (3,4-dimethylphenylsulfonyl) phenol, 2,4-bis (4-chlorophenylsulfonyl) phenol 2,4-bis (phenylsulfonyl) -5-methylphenol, 2,4-bis (4-methylphenylsulfonyl) -5-methylphenol,
2,4-bis (phenylsulfonyl) -5-ethylphenol, 2,4-bis (4-methylphenylsulfonyl) -5-ethylphenol, 2,4bis (2,4-dimethylphenylsulfonyl) -5-methyl Phenol,
2,4bis (2,5-dimethylphenylsulfonyl)-
5-methylphenol, 2,4-bis (3,4-dimethylphenylsulfonyl) -5-methylphenol, 2-methylphenol
(4-methylphenylsulfonyl) -4- (phenylsulfonyl) phenol, 2- (4-ethylphenylsulfonyl) -4- (phenylsulfonyl) phenol, 2
-(2,5-dimethylphenylsulfonyl) -4- (phenylsulfonyl) phenol, 2- (2,4-dimethylphenylsulfonyl) -4- (phenylsulfonyl)
Phenol, 2- (3,4-dimethylphenylsulfonyl) -4- (phenylsulfonyl) phenol, 2-
(4-chlorophenylsulfonyl) -4- (phenylsulfonyl) phenol, 2- (phenylsulfonyl)-
4- (4-methylphenylsulfonyl) phenol, 2
-(Phenylsulfonyl) -4- (4-ethylphenylsulfonyl) phenol, 2- (phenylsulfonyl)
-4- (2,5-dimethylphenylsulfonyl) phenol, 2- (phenylsulfonyl) -4- (2,4-dimethylphenylsulfonyl) phenol, 2- (phenylsulfonyl) -4- (3,4-dimethylphenyl Sulfonyl) phenol, 2- (phenylsulfonyl) -4
-(4-chlorophenylsulfonyl) phenol, 4,
4'-dihydroxy-5- (phenylsulfonyl) diphenylsulfone or 4,4'-dihydroxy-5,5 '
The sulfonyl compound according to claim 1, which is -bis (phenylsulfonyl) diphenylsulfone, and a polyvalent metal salt thereof. 3. A developer used in a heat-sensitive recording material utilizing a color development reaction between an electron-donating basic dye precursor and an electron-accepting color developer according to the general formula (1) according to claim 1. A developer for a thermosensitive recording material, comprising at least one selected from the sulfonyl compounds and polyvalent metal salts thereof. 4. A developer used in a thermosensitive recording material utilizing a color development reaction between an electron-donating basic dye precursor and an electron-accepting color developer, represented by the general formula (1) according to claim 1. And at least one selected from the sulfonyl compounds and polyvalent metal salts thereof, and a compound represented by the general formula (2): [In the general formula (2), R ₈ and R ₉ may be the same or different and each represents a hydrogen atom, a lower alkyl group or a lower alkylene group, and R ₁₀ represents a hydrogen atom or a linear or branched lower alkyl group. Y represents a sulfonyl group, a lower alkylene group or a lower alkylidene group, and n represents 0 or 1. And a mixture with at least one selected from diphenyl derivatives represented by the formula: 5. The diphenyl derivative represented by the general formula (2) is 2,2-bis (4-hydroxy-phenyl) propane, 4-hydroxy-4'-isopropoxy-diphenyl sulfone, 4,4'-dihydroxy The compound according to claim 4, which is -diphenylsulfone, bis (3-allyl-4-hydroxy-phenyl) sulfone, 4-hydroxy-2 ', 5'-dimethyl-diphenylsulfone or 2-methyl-4-hydroxy-diphenylsulfone. Developer for thermal recording materials. 6. A heat-sensitive recording material comprising the color developer according to claim 3 in a color-developing recording layer.